CN103615993B - Based on micro-structural test macro and method from axle micro-interference art - Google Patents

Abstract

A kind of micro-structural test macro and method based on from axle micro-interference art, comprise LASER Light Source, on the output optical axis of LASER Light Source, be provided with light-splitting device, on a light output shaft of light-splitting device, be provided with the first collimator and extender device, on the light output shaft of the first collimator and extender device, be provided with Amici prism, on another light output shaft of light-splitting device, be provided with the first speculum, on the reflection optical axis of the first speculum, be provided with the second collimator and extender device, on the light output shaft of the second collimator and extender device, be provided with the second speculum, the corresponding Amici prism of reflection optical axis of the second speculum, in the light path that the first collimator and extender device is exported by Amici prism, be provided with for irradiating tested sample and collecting the microcobjective of tested sample surface reflection object light, the corresponding CCD that is provided for opto-electronic conversion on the output light path of Amici prism, another end points linking number word image pick-up card of CCD. the present invention only needs a width interference pattern can reach the object that Microstructures Topography is measured, and can realize real-time dynamic test.

Description

Based on micro-structural test macro and method from axle micro-interference art

Technical field

The present invention relates to a kind of microstructure appearance test macro. Particularly relate to a kind of by tilt reference ripple from axle micro-interferenceBased on micro-structural test macro and method from axle micro-interference art.

Background technology

MEMS (MEMS), Micrometer-Nanometer Processing Technology and nanometer technology are rapid at contemporary development, sought-after, therefore micro-Structured testing receives much attention, and measures and requires also progressively to improve. For MEMS device, its electronics test is no doubt important, but micro-Multiple ginsengs such as construction geometry amount, mechanical quantity, Mechanics of Machinery characteristic, material behavior, optical characteristics, acoustic characteristic and magnetism characteristicThe test of number is also essential. And the processing technology complexity of Microstructures Topography, often by machining, chemical process withAnd other special processing process form. Meet at needs on the processing request of surface topography directly perceived, the surface topography of micro-structural alsoAs closely related in physicochemical properties such as hardness, residual stress, chemical composition, material behaviors with material intrinsic characteristic, these spiesProperty all can produce direct or indirect impact to the serviceability of micro-structural. Therefore for MEMS Microstructures Topography geometric senseTest particularly important. The measurement category of test macro, the raising of measuring speed and certainty of measurement is that MEMS measuring technology is enteredThe great embodiment of step.

Because MEMS device architecture is meticulous, its feature structural dimension parameter is generally in micro-nano magnitude, if therefore to obtain comparatively accurateMeasurement result, the precision of its test structure and pattern also should be in micro-nano magnitude. This is to measuring technology and measurement device precisionIt is also higher requiring. And for some dynamic device, its topography measurement also has the requirement of real-time. Microscopic interferometryA kind of principle based on coherent light interference, in conjunction with microscopic system, by extract effective phase bit recovery of micro-structural in interference patternA kind of measuring method of measured object pattern. There is the advantages such as noncontact, high sensitivity, high accuracy due to it, thereby in micro-structuralBe used widely in geometry test field. Micro-interference mainly comprises phase shift interference, white light interference etc. Phase-shift interferometryUse monochromatic light as light source, need the micrometric displacement scanning of the step pitches such as phase-shifter, record several (at least three width) interference pattern abilityObtain relevant phase place. And white light interferometric method uses white light as light source, according to white light interference principle, by measured piece is enteredThe position of every bit zero optical path difference under the sweep record of row vertical direction, obtains measured piece surface three dimension information. For above two kindsMethod, the requirement of interference pattern quantity, the precision of phase-shifter and expensive price and to characteristic limitations such as vibration sensings theyApplication. And micro-interference in theory only needs a width interference pattern in conjunction with the measuring method of Fourier transformation, if but application biographyThe device of system micro-interference, must just can reach the object that increases carrier frequency by inclination sample, obtains measurement result accurately.If sample tilt angle is crossed conference, interference region is dwindled, available field of view's scope can seriously be shunk, and therefore sample tilt angle is limited,This just causes carrier frequency deficiency, and the phenomenon of spectrum overlapping occurs, and needs more width interference patterns to rectify thereby therefore reversion also occurs phase placeJust, make measurement more complicated. This method that also shows conventional micro-interference is measured and is required or be difficult for for the real-time of micro-structuralReach. Therefore, how in ensureing high-acruracy survey, to improve and measure efficiency, reduce the dependence to interference pattern quantity, realThe real-time of now measuring, becomes micro-interference measurement and is applied to microstructure appearance field tests problem demanding prompt solution, is also itThe trend of exhibition.

Summary of the invention

Technical problem to be solved by this invention is, provide a kind of can realize full visual field, noncontact, quick high accuracy based onFrom micro-structural test macro and the method for axle micro-interference art.

The technical solution adopted in the present invention is: a kind of micro-structural test macro based on from axle micro-interference art, comprises laser lightSource is provided with light-splitting device on the output optical axis of LASER Light Source, on a light output shaft of described light-splitting device, is provided withThe first collimator and extender device, is provided with Amici prism on the light output shaft of described the first collimator and extender device, at described light-splitting deviceOn another light output shaft, be provided with the first speculum, on the reflection optical axis of described the first speculum, be provided with the second collimator and extender device,On the light output shaft of described the second collimator and extender device, be provided with the second speculum, described in the reflection optical axis correspondence of described the second speculumAmici prism, is provided with for irradiating tested sample and receipts in the light path that the first described collimator and extender device is exported by Amici prismThe microcobjective of collection tested sample surface reflection object light, the corresponding opto-electronic conversion that is provided on the output light path of described Amici prismCCD, another end points linking number word image pick-up card of described CCD.

Described light-splitting device adopts Amici prism or adopts polarization splitting prism.

In the time that described light-splitting device adopts polarization splitting prism, the optical axis between described LASER Light Source and described light-splitting deviceOn be provided with the first half-wave plate, on the optical axis between described light-splitting device and described the first collimator and extender device, be provided with the second halfWave plate.

On optical axis between the first described collimator and extender device and described Amici prism, be provided with first lens.

In light path between the second described speculum and described Amici prism, be provided with the second lens.

The optical axis of the tested sample surface reflection object light that the reverberation of the second described speculum and described Amici prism are exportedBe formed with off-axis angle θ, described off-axis angle θ is 1～6 °.

For a method for the micro-structural test macro based on from axle micro-interference art, comprise the steps:

1) laser light source being sent becomes two bundle coherent lights by light splitting, object light reflexing to through tested sample in coherent lightReach CCD, interfere and form interference pattern with the reference light that incides CCD, described reference light is by the speculum in light pathThe optical axis of the object light that after regulating, the reverberation of output receives with CCD becomes certain off-axis angle θ, increases carrier frequency, ensures from axleInterfere;

2) using the minute surface of a plane mirror as ideally-reflecting face, record plane mirror minute surface from axle interference pattern, to instituteThat states carries out Fourier transformation from axle interference pattern, to carrying out spectral filtering from axle interference pattern, obtains including reference light phase place and isThe interference term of the ideally-reflecting face of the optical distortion phase place that system is introduced, and carry out the interference term of ideally-reflecting face as systematic errorRecord, using this step 2) record that obtains eliminates the reference of systematic error later in measuring each time, and afterwards everyIn one-shot measurement, skip this step 2), no longer duplicate record;

3) be positioned in light path micro element as tested sample, gather from axle interference pattern record, to gathered doing from axleRelate to figure and carry out Fourier transformation, through to the spectral filtering from axle interference pattern, obtain including micro element pattern phase place, reference lightThe interference term of the optical distortion phase place that phase place and system are introduced;

4) systematic error is carried out to conjugation calculating, the interference term of gained micro element in result of calculation and step 3) is multiplied each other, eliminateWith step 2) the corresponding systematic error of systematic error that records, obtain the real topography phase place of micro element, then pass through phaseThe surface topography information of position and the proportionate relationship recovery micro element of height.

Step 2) and step 3) described in to from axle interference pattern intensity distribution being:

i(x,y)=a(x,y)+O(x,y)R^*(x,y)+O^*(x,y)R(x,y)=a(x,y)+c(x,y)+c^*(x,y)（1）

In formula, a (x, y) is direct transmission light item, the COMPLEX AMPLITUDE that O (x, y) is object light, and the COMPLEX AMPLITUDE that R (x, y) is reference light,^*RepresentativeConjugation is calculated, and described carried out to spectral filtering from axle interference pattern, obtains step 2) and step 3) described in to interfering from axleThe interference term c (x, y) of figure.

Elimination and step 2 described in step 4)) the corresponding systematic error of systematic error that records, be by step 2) noteThe conjugation item of the systematic error interference term of record and the following formula of micro element interference term that step 3) leaches multiply each other, and reach elimination systemThe object of error:

$\begin{array}{c}c(x,y)\×{c^{*}}_{\mathrm{plane}}(x,y)\\ =[O(x,y)\×R(x,y)]\×{[O_{\mathrm{plane}}(x,y)\×R(x,y)]}^{*}\\ =\left\{\right[A_O\×\exp ({\mathrm{\φ}}_{\mathrm{aberration}}(x,y)+{\mathrm{\φ}}_{\mathrm{sample}}(x,y))]\×A_R\×\exp \left({\mathrm{\φ}}_R(x,y)\right)\}\\ \×{\left\{\right[A_{O_{\mathrm{plane}}}\×\exp \left({\mathrm{\φ}}_{\mathrm{aberration}}(x,y)\right)]\×A_R\×\exp \left({\mathrm{\φ}}_R(x,y)\right)\}}^{*}\\ =A\×\exp \left({\mathrm{\φ}}_{\mathrm{sample}}(x,y)\right)\end{array}---\left(2\right)$

In formula, the interference term that c (x, y) is micro element, c^* _planeThe conjugation item of the interference term that (x, y) is ideally-reflecting face, O (x, y) isThe COMPLEX AMPLITUDE of the object light of micro element, the COMPLEX AMPLITUDE that R (x, y) is reference light, O_plane(x, y) is the thing for ideally-reflecting faceRecovery distribution of amplitudes, φ_aberrationThe distortion phase place that (x, y) introduces for optical system, φ_sample(x, y) and φ_R(x, y) differenceFor the sample phase place of micro element and the phase place of reference light, A_O，A_RWithThe object light of micro element, reference light and ideally-reflectingThe object light amplitude of face.

Phase place described in step 4) adopts following formula to obtain with the proportionate relationship of height:

$h=\frac{{\mathrm{\φ}}_{\mathrm{sample}}(x,y)\×\mathrm{\λ}}{4\mathrm{\π}}---\left(3\right)$

In formula, h is the pattern height of micro element, φ_sample(x, y) is micro element phase place, and λ is the wavelength of light source.

Micro-structural test macro and method based on from axle micro-interference art of the present invention, does not have from the measurement mechanism of axle micro-interferenceApply the interference microscope in common micro-interference system, but with Mach-Zehnder interferometer replacement, can adjust neatly referenceThe off-axis angle of light, increases carrier frequency, the interference term that contains effective measured object pattern phase place can be separated with zero-order term, through overfrequencySpectral filter Systematic Error Correction etc. obtains measured object phase place information, makes this measuring method only need a width interference pattern can reach micro-The object of body structure surface topography measurement, can realize real-time dynamic test. The present invention also has following features:

1, measuring system makes reference light direction become certain off-axis angle to reach with inclined light shaft by accommodation reflex mirror to increase carrier frequencyObject.

2, measuring system is interfered on the basis that obtains phase place and has been ensured the long reach of microcobjective in microscopic magnifying apparatus in utilizationCharacteristic.

3, measuring system only needs a microcobjective.

Brief description of the drawings

Fig. 1 is the micro-structural test macro formation schematic diagram based on from axle micro-interference art of the present invention;

Fig. 2 is systematic error figure;

Fig. 3 be micro-step from axle micro-interference figure;

Fig. 4 is the spectrogram of interference pattern;

Fig. 5 is the micro-step appearance figure that contains systematic error;

Fig. 6 is the micro-step appearance figure that eliminates error;

Fig. 7 is the cell morphology figure recording from axle micro-interference;

Fig. 8 is the high carrier frequency micropore interference pattern that Mirau micro-interference system obtains;

Fig. 9 is the cell morphology figure that Mirau micro-interference system obtains.

In figure

1: 2: the first half-wave plates of LASER Light Source

3: 4: the first speculums of light-splitting device

6: the first collimator and extender devices of 5: the second half-wave plates

7: 8: the second collimator and extender devices of first lens

10: the second lens of 9: the second speculums

11: Amici prism 12: microcobjective

13: tested sample 14:CCD

15: digital image acquisition card 16: computer

Detailed description of the invention

Below in conjunction with embodiment and accompanying drawing to of the present invention based on making in detail from micro-structural test macro and the method for axle micro-interference artDescribe in detail bright.

As shown in Figure 1, the micro-structural test macro based on from axle micro-interference art of the present invention, comprises LASER Light Source 1, is swashingOn the output optical axis of radiant 1, be provided with light-splitting device 3, described light-splitting device 3 can adopt Amici prism or adopt polarizationAmici prism. On a light output shaft of described light-splitting device 3, be provided with the first collimator and extender device 6, described the first collimationOn the light output shaft of beam expander 6, be provided with Amici prism 11, on another light output shaft of described light-splitting device 3, be provided withThe first speculum 4, is provided with the second collimator and extender device 8 on the reflection optical axis of described the first speculum 4, described the second collimator and extenderOn the light output shaft of device 8, be provided with the second speculum 9, the corresponding described Amici prism 11 of reflection optical axis of described the second speculum 9,On the parallel light path that the first described collimator and extender device 6 is exported by Amici prism 11, be provided with for irradiating tested sample 13 HesThe microcobjective 12 of collecting tested sample 13 surface reflection object lights, on the output light path of described Amici prism 11, correspondence is provided forThe CCD14 of opto-electronic conversion, another end points linking number word image pick-up card 15 of described CCD14. The second described speculumThe optical axis of the tested sample 13 surface reflection object lights that 9 reverberation and described Amici prism 11 are exported is formed with off-axis angleθ, described off-axis angle θ is 1～6 °.

In the time that described light-splitting device 3 adopts polarization splitting prism, between described LASER Light Source 1 and described light-splitting device 3Optical axis on be provided with the first half-wave plate 2, on the optical axis between described light-splitting device 3 and described the first collimator and extender device 6Be provided with the second half-wave plate 5.

On optical axis between the first described collimator and extender device 6 and described Amici prism 11, also can be provided with first lens 7. InstituteIn light path between the second speculum 9 of stating and described Amici prism 11, also can be provided with the second lens 10.

In the present embodiment, described LASER Light Source 1 adopts CrystaLaser, the light source of CL640-050-S; Described micro-thingMirror 12 adopts Mitutoyo, NA=0.42, enlargement ratio 50 × microcobjective; CCD14 adopts Imperx, PX-2M30-L,1008 × 1028, Pixel Dimensions 7.4 m, the CCD of 33 frame/seconds.

The operation principle of the micro-structural test macro based on from axle micro-interference art of the present invention is: the list sending from LASER Light Source 1Coloured light, through the combination of the first half-wave plate 2 and polarization splitting prism 3, is divided into the orthogonal two bunch polarizations in polarization direction relevantLight. Object light in coherent light is by the second half-wave plate 5, and polarization direction transfers to identical with object light. Object light and reference light pass through respectivelyThe first collimator and extender device 6, the second collimator and extender device 8 expand, collimation. Object light is through first lens 7 Hes on object light armMicrocobjective 12 forms directional light and impinges perpendicularly on tested sample 13 surfaces, and the object light of tested sample 13 surface reflections continues to be shownSpeck mirror 12 is collected, and arrives CCD by Amici prism 11 with the form of spherical wave, for CCD receives. After collimator and extenderReference light sees through the second lens 10 on reference arm, also arrives at CCD with the form of spherical wave, CCD surface with carry byThe object light of this surface topography of test sample information interferes. Interference pattern is by CCD record. Adjust the second speculum 9 on reference armAngle, make reference light direction become an off-axis angle θ with optical axis, ensure interfere from axle.

Method for the micro-structural test macro based on from axle micro-interference art of the present invention, comprises the steps:

1) laser light source being sent becomes two bundle coherent lights by light splitting, object light reflexing to through tested sample in coherent lightReach CCD, interfere and form interference pattern with the reference light that incides CCD, described reference light is by the speculum in light pathThe optical axis of the object light that after regulating, the reverberation of output receives with CCD becomes certain off-axis angle θ, increases carrier frequency, ensures from axleInterfere;

2) using the minute surface of a plane mirror as ideally-reflecting face, record plane mirror minute surface from axle interference pattern, to instituteThat states carries out Fourier transformation from axle interference pattern, to carrying out spectral filtering from axle interference pattern, obtains the interference term of ideally-reflecting face,And carry out record using the interference term of ideally-reflecting face as systematic error, and using this step 2) record that obtains is as each time laterIn measurement, eliminate the reference of systematic error, correct for phase place afterwards. And skip this step in measurement each time afterwards2), no longer duplicate record, Fig. 2 is systematic error figure;

3) be positioned in light path micro element as tested sample, gather from axle interference pattern record, to gathered doing from axleRelate to figure and carry out Fourier transformation, through to the spectral filtering from axle interference pattern, obtain including tested sample pattern phase place, referenceThe interference term of the optical distortion phase place that light phase and system are introduced;

Tested micro element sample is placed in to systematic sample position, gather tested sample from axle micro-interference figure, as shown in Figure 3.In figure, amplifier section is the interference fringe with high carrier frequency, corresponding to above-mentioned steps 2) and step 3) described in to interfering from axleFigure intensity distribution is:

i(x,y)=a(x,y)+O(x,y)R^*(x,y)+O^*(x,y)R(x,y)=a(x,y)+c(x,y)+c^*(x,y)（1）

In formula, a (x, y) is direct transmission light item, the COMPLEX AMPLITUDE that O (x, y) is object light, and the COMPLEX AMPLITUDE that R (x, y) is reference light,^*RepresentativeConjugation is calculated. Described carried out to spectral filtering from axle interference pattern, obtains step 2) and step 3) described in to interfering from axleThe interference term c (x, y) of figure.

4) systematic error is carried out to conjugation calculating, the interference term of gained micro element in result of calculation and step 3) is multiplied each other, eliminateWith step 2) the corresponding systematic error of systematic error that records, obtain the real topography phase place of micro element, then pass through phaseThe surface topography information of position and the proportionate relationship recovery micro element of height.

Fig. 4 is the spectrogram after interference pattern Fourier transformation. Carry the c (x, y) of object light phase information due to the carrier frequency of reference lightEnough large, therefore can be leached with simple window function spectral filtering, then be obtained containing systematic error through inverse Fourier transformAnd the shape appearance figure of sample elevation information, as shown in Figure 5. By the conjugation item of the systematic error interference term of record with leach testedSample interference term multiplies each other, and can reach the object of eliminating systematic error.

Described elimination and step 2) the corresponding systematic error of systematic error that records, be by step 2) system of recordThe conjugation item of error interference term and the following formula of micro element interference term that step 3) leaches multiply each other, and reach the order of eliminating systematic error:

$\begin{array}{c}c(x,y)\×{c^{*}}_{\mathrm{plane}}(x,y)\\ =[O(x,y)\×R(x,y)]\×{[O_{\mathrm{plane}}(x,y)\×R(x,y)]}^{*}\\ =\left\{\right[A_O\×\exp ({\mathrm{\φ}}_{\mathrm{aberration}}(x,y)+{\mathrm{\φ}}_{\mathrm{sample}}(x,y))]\×A_R\×\exp \left({\mathrm{\φ}}_R(x,y)\right)\}\\ \×{\left\{\right[A_{O_{\mathrm{plane}}}\×\exp \left({\mathrm{\φ}}_{\mathrm{aberration}}(x,y)\right)]\×A_R\×\exp \left({\mathrm{\φ}}_R(x,y)\right)\}}^{*}\\ =A\×\exp \left({\mathrm{\φ}}_{\mathrm{sample}}(x,y)\right)\end{array}---\left(2\right)$

In formula, the interference term that c (x, y) is micro element, c^* _planeThe conjugation item of the interference term that (x, y) is ideally-reflecting face, O (x, y) isThe COMPLEX AMPLITUDE of the object light of micro element, the COMPLEX AMPLITUDE that R (x, y) is reference light, O_plane(x, y) is the thing for ideally-reflecting faceRecovery distribution of amplitudes, φ_aberrationThe distortion phase place that (x, y) introduces for optical system, φ_sample(x, y) and φ_R(x, y) differenceFor the sample phase place of micro element and the phase place of reference light, A_O，A_RWithThe object light of micro element, reference light and ideally-reflectingThe object light amplitude of face.

Described phase place adopts following formula to obtain with the proportionate relationship of height:

$h=\frac{{\mathrm{\φ}}_{\mathrm{sample}}(x,y)\×\mathrm{\λ}}{4\mathrm{\π}}---\left(3\right)$

In formula, h is the pattern height of micro element, φ_sample(x, y) is micro element phase place, and λ is the wavelength of light source.

Final sample pattern height is drawn by (3) formula. Fig. 6 is by the real topography figure of micrometer step. It effectively measures visual fieldBe 149 μ m × 152 μ m. Meanwhile, native system is also tested a microwell array, the shape appearance figure that Fig. 7 is gained.

Of the present invention based on can obtain the dry of higher more sufficient carrier frequency from the micro-structural test macro of axle micro-interference art in order to proveRelate to figure, we do comparative illustration by the result that traditional Mirau interference objective records. For obtaining the interference pattern of high carrier frequency, passingIn system micro-interference system, need sample to tilt, as shown in Figure 8, this is the interference pattern of microwell array in Fig. 7. Can find outAn interference fringe visual field, cover part. And what obtain after this width interference pattern is processed is strained shape appearance figure, as Fig. 9Shown in. Application conventional interference object lens, even inclination sample, the carrier frequency of interference pattern remains inadequate.

Claims (4)

1. for a method for the micro-structural test macro based on from axle micro-interference art, it is characterized in that, described based onFrom the micro-structural test macro of axle micro-interference art, comprise LASER Light Source (1), on the output optical axis of LASER Light Source (1), establishBe equipped with light-splitting device (3), on a light output shaft of described light-splitting device (3), be provided with the first collimator and extender device (6),On the light output shaft of described the first collimator and extender device (6), be provided with Amici prism (11), at described light-splitting device (3)On another light output shaft, be provided with the first speculum (4), on the reflection optical axis of described the first speculum (4), be provided with secondCollimator and extender device (8), is provided with the second speculum (9) on the light output shaft of described the second collimator and extender device (8), and describedThe corresponding described Amici prism of reflection optical axis (11) of two-mirror (9), the first described collimator and extender device (6) is by light splittingIn the light path of prism (11) output, be provided with for irradiating tested sample (13) and collecting tested sample (13) surface reflection thingThe microcobjective (12) of light, the corresponding CCD (14) that is provided for opto-electronic conversion on the output light path of described Amici prism (11),Another end points linking number word image pick-up card (15) of described CCD (14), described method comprises the steps:

1) laser light source being sent becomes two bundle coherent lights by light splitting, object light reflexing to through tested sample in coherent lightReach CCD, interfere and form interference pattern with the reference light that incides CCD, described reference light is by the speculum in light pathThe optical axis of the object light that receives with CCD of reverberation of output after regulating becomes certain off-axis angle θ, increases carrier frequency, guarantee fromAxle is interfered;

2) using the minute surface of a plane mirror as ideally-reflecting face, record plane mirror minute surface from axle interference pattern, to instituteThat states carries out Fourier transformation from axle interference pattern, to carrying out spectral filtering from axle interference pattern, obtains including reference light phase place and isThe interference term of the ideally-reflecting face of the optical distortion phase place that system is introduced, and carry out the interference term of ideally-reflecting face as systematic errorRecord, using this step 2) record that obtains eliminates the reference of systematic error later in measuring each time, and afterwards everyIn one-shot measurement, skip this step 2), no longer duplicate record;

3) be positioned in light path micro element as tested sample, gather from axle interference pattern record, to gathered doing from axleRelate to figure and carry out Fourier transformation, through to the spectral filtering from axle interference pattern, obtain including micro element pattern phase place, reference lightThe interference term of the optical distortion phase place that phase place and system are introduced;

4) systematic error is carried out to conjugation calculating, by result of calculation and step 3) in the interference term of gained micro element multiply each other, disappearExcept and step 2) the corresponding systematic error of the systematic error that records, obtain the real topography phase place of micro element, then pass throughThe proportionate relationship of phase place and height is recovered the surface topography information of micro element.

2. the method for the micro-structural test macro based on from axle micro-interference art according to claim 1, its featureBe step 2) and step 3) described in to from axle interference pattern intensity distribution being:

i(x,y)＝a(x,y)+O(x,y)R^*(x,y)+O^*(x,y)R(x,y)＝a(x,y)+c(x,y)+c^*(x,y)(1)

In formula, a (x, y) is direct transmission light item, the COMPLEX AMPLITUDE that O (x, y) is object light, and the COMPLEX AMPLITUDE that R (x, y) is reference light,^*RepresentativeConjugation is calculated, and described carried out to spectral filtering from axle interference pattern, obtains step 2) and step 3) described in to doing from axleRelate to the interference term c (x, y) of figure.

3. the method for the micro-structural test macro based on from axle micro-interference art according to claim 1, its featureBe step 4) described in elimination and step 2) the corresponding systematic error of systematic error that records, be by step 2)Conjugation item and the step 3 of systematic error interference term of record) the following formula of micro element interference term that leaches multiplies each other, reaches to eliminate to beThe object of system error:

$\begin{array}{c}c\left(x,y\right)\×{c^{*}}_{plane}\left(x,y\right)\\ =\[O\left(x,y\right)\×R\left(x,y\right)\]\×{\[O_{plane}\left(x,y\right)\×R\left(x,y\right)\]}^{*}\\ =\left\{\[A_O\×\exp \left({\mathrm{\φ}}_{aberration}\left(x,y\right)+{\mathrm{\φ}}_{sample}\left(x,y\right)\right)\]\×A_R\×\exp \left({\mathrm{\φ}}_R\left(x,y\right)\right)\right\}\\ \×{\left\{\[A_{O_{plane}}\×\exp \left({\mathrm{\φ}}_{aberration}\left(x,y\right)\right)\]\×A_R\×\exp \left({\mathrm{\φ}}_R\left(x,y\right)\right)\right\}}^{*}\\ =A\×\exp \left({\mathrm{\φ}}_{sample}\left(x,y\right)\right)\end{array}---\left(2\right)$

In formula, the interference term that c (x, y) is micro element, c^* _planeThe conjugation item of the interference term that (x, y) is ideally-reflecting face, O (x, y)For the COMPLEX AMPLITUDE of the object light of micro element, the COMPLEX AMPLITUDE that R (x, y) is reference light, O_plane(x, y) is for being ideally-reflecting faceObject light COMPLEX AMPLITUDE, φ_aberrationThe distortion phase place that (x, y) introduces for optical system, φ_sample(x, y) and φ_R(x,y)Be respectively the sample phase place of micro element and the phase place of reference light, A_O，A_RWithThe object light of micro element, reference light and idealThe object light amplitude of reflecting surface.

4. the method for the micro-structural test macro based on from axle micro-interference art according to claim 1, its featureBe step 4) described in phase place with height proportionate relationship adopt following formula obtain:

$h=\frac{{\mathrm{\φ}}_{sample}(x,y)\×\mathrm{\λ}}{4\mathrm{\π}}---\left(3\right)$

In formula, h is the pattern height of micro element, φ_sample(x, y) is micro element phase place, and λ is the wavelength of light source.